MAE SOT , Thailand -LRB- CNN -RRB- -- A Myanmar rebel leader killed in February said that his group is fighting for the preservation of the ethnic Karen minority , and for greater freedom throughout the southeast Asian nation .

Mahn Sha is seen at his home in Thailand shortly before his slaying in February .

Pa Doh Mahn Sha , the secretary-general of the Karen National Union -LRB- KNU -RRB- , spoke in an interview three weeks before his death . He talked about his group 's battle against Myanmar 's military government .

`` Our struggle is to protect ourselves from the military regime , '' he said . `` They always attack our villages , burn down our villages , burn our food supplies . We want to stop fighting but we have no choice . ''

The government of Myanmar has blamed the KNU for waging attacks to destabilize the military junta .

Mahn Sha was shot and killed at his home in Thailand on February 14 , a KNU official said . During one of the last interviews Mahn Sha granted to international journalists , he posed in front of the Karen national flag hanging in his living room , and talked about the future of the Karen people and the KNU 's fight for autonomy .

He said the KNU 's fighters would continue to battle the military junta in self-defense . `` Our struggle is the same struggle as the monks who protested in September , the same struggle as -LSB- pro-democracy activist -RSB- Aung San Suu Kyi , '' he said . `` Only in a different form , ours is a violent struggle , and we can not give up until we have won . ''

The 64-year-old Mahn Sha was shot and killed in Mae Sot , Thailand , just across the border from Myanmar , a KNU official said . As Thai police investigate his killing , speculation has varied on how the Karen leader was killed .

There have been suggestions the killing may have been the result of internal differences within the rebel group . But some Karen blame Myanmar 's military junta . The government has not commented .

The killing came just days after Myanmar announced plans for a referendum on a new constitution , to be followed by a general election in 2010 as part of its `` road map to democracy . '' The plan has been denounced by pro-democracy opposition leaders .

A charismatic leader mourned

Mahn Sha was the KNU 's third in command , but widely respected as the group 's acting leader , said KNU Foreign Affairs spokesperson David Taw . His death is viewed by many as a major setback for the already struggling resistance movement .

`` Mahn Sha -LSB- was -RSB- the strong guiding light , '' said Oscar Baaye , an ethnic Karen from the United States who was living with Mahn Sha prior to the rebel leader 's death .

Mahn Sha had been described as a skilled mediator between different Karen factions , as well as other ethnic groups in the region and those working for democracy in Myanmar .

`` Mahn Sha 's assassination was a blow to the entire democracy process , '' said Aung Zaw , editor of the Irrawaddy magazine . `` A lot of people saw him as a potential figure to work on national reconciliation . He was able to connect the Karen struggle to the bigger picture , '' he said .

`` He built bridges between all groups , that was one of his strengths , '' said Phil Thornton , author of Restless Souls , who has been reporting on the Karen for seven years and lives in Mae Sot .

Young Karen , in particular , said they felt inspired by Mahn Sha 's approach to the democracy movement in Myanmar . `` He had a very clear vision of our struggle , '' said Nicky Zaw , who attended Mahn Sha 's funeral .

Dwindling numbers

The KNU 's military , a ragtag group of soldiers who often wield World War II weaponry , has come under criticism , accused of recruiting child soldiers and carrying on what many have called an unwinnable war in civilian-occupied territory . The KNU has denied using child soldiers .

In his interview , Mahn Sha said that the KNU had the support and backing of the villagers who are caught in the middle of this conflict .

`` The military regime might have big numbers , but they do n't have the support of the people , '' he said , claiming that for every KNU soldier there are at least 25 government soldiers . `` We can protect them because we have their support , '' he said .

Still , humanitarian groups such as the Free Burma Rangers regularly report attacks in Karen villages by the military regime carrying out counterinsurgency operations . Thousands have fled the fighting .

Prior to his death , Mahn Sha had just returned from a Karen Unity Seminar , in which Karen from around the world gathered at a secret headquarters in Myanmar to discuss the future of their movement and their people .

The KNU has been fighting the government of Myanmar for about 60 years , since shortly after the departure of the British from the country then known as Burma in 1948 . It is one of the world 's longest-running insurgencies .

But during the past decade , their troop numbers have dwindled from 20,000 to a mere 4,000 , said David Taw . The KNU has suffered huge losses as members tire of war and resettle in places such as Europe and the United States , he said .

The group also still suffers from crippling infighting and another splinter group , a faction commonly called the Karen National Union Peace Council , recently broke ranks to sign a peace agreement with the government of Myanmar -- like many other groups .

While KNU leaders have been clear that they will continue their battle against Myanmar 's military regime , they say the loss of Mahn Sha was a huge blow for the movement .

At Mahn Sha 's funeral , more than 1,000 mourners gathered in the jungle inside Myanmar , including representatives from nearly every regional ethnic group and Aung San Suu Kyi 's National League for Democracy party . E-mail to a friend

Journalist Jonathan Jones contributed to this report .

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Slain Myanmar rebel leader gave interview out days before assassination

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Mahn Sha said rebel fighters are fighting same struggle as democracy activists

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Speculation has ranged widely on cause of Karen leader 's slaying

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Myanmar ruling junta has not commented on Mahn Sha 's death